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Save 61% on fuel costs by converting your car to a plug-in hybrid

New technology has been designed that allows your conventionally-engined car to be converted to a hybrid. It can save you even more on fuel than a normal hybrid, as it can be plugged in to your electricity to recharge the extra battery. However even if you don’t have off street parking, you can still use this system, as you take the battery out of the car and take it into your house to plug it in to your electricity.

As this is a retro-fit conversion, your existing car can benefit from the technology. It’s designed by MIRA and they claim their system, with a removable battery pack, can save 61% on fuel costs, and reduce tailpipe emissions by 39%.

As a “plug-in hybrid” the vehicle can charge its batteries by running its engine or by plugging into the mains.

The demonstrator vehicle is based on the Skoda Fabia. The 50/50 hybrid derives power jointly from a 60Kw petrol engine at the front and two 35KW inboard motors powering the rear wheels though MIRA’s e-differential. The car is a Hybrid 4wd Vehicle – so it’s called the H4V. The demonstrator differentiates itself from the standard model by returning 64mpg on the combined cycle – a 61% improvement relative to the standard model (which returns 39mpg combined), whilst general levels of performance, such as top speed and acceleration are similar to standard.

The car has a battery pack that is arranged into 3 portable cassettes, each capable of storing 30KW. These storage units could also power external devices, including a range of lifestyle accessory items. The very latest nano-particle technology has been applied to increase the energy density of the already ‘high-tech’ Lithium Ion Phosphate batteries. This ensures the energy pack is as lightweight and compact as possible, whilst delivering superior voltage stability over the charge range. The same Li-Ion Phosphate battery technology is evident in the separate low voltage circuit used to start the engine, ensuring the car’s impeccable ‘lead free’ green credentials.

The ultimate aim of the project team is to see the power pack transferred from the car into a range of other devices, which could include camping equipment for SUV variants, or redeployed to power electric jet skis or quad bikes.

The base car needs modern features, such as a throttle by-wire system and some other basics, to avoid duplicating unnecessary workload.

A 39% improvement in emissions is beyond what most traditional hybrid systems would normally deliver, as MIRA have retuned the engine and created a custom calibration that works with the electrically driven axle to deliver additional fuel savings.

Philip Sellwood, Chief Executive of the Energy Saving Trust, which is managing the initiative said: “This project has designed a new system allowing hybrids to be more flexible and practical for every day use. With over 20% of the UK’s total carbon emission produced by road transport every year, these advances in technology are vital. Over 80% of people believe that climate change is having an impact on the UK right now, so it is important to bring more technology like these to the market place.”

Commenting on the new design Transport Minister Jim Fitzpatrick said: “With the challenges of climate change, we need to find opportunities to contribute positively to protecting our environment. Working with the Energy Saving Trust has been just such an opportunity, and I’m delighted that funding from the DfT’s Low Carbon R&D programme has been put to good use in developing an efficient petrol hybrid car.

Road transport is key in our efforts to cut carbon, and bringing cleaner vehicles on to the market is vital to achieving this goal. I understand that MIRA have comfortably exceeded their emission target after tests, which is a really encouraging result, and I look forward to hearing more good news about the programme.”

Derek Charters, MIRA’s Advanced Powertrain Manager explains the rationale behind the project: “Despite advances in powertrain technology you can still obtain electricity from your domestic provider far cheaper and greener than you can produce it via an automotive combustion engine, so ‘plug-in’ hybrids make sense. With this project we’ve removed the primary limitation of the ‘plug-in hybrid’ concept by allowing the battery pack to come to the mains, rather than having to park right next to a socket …which is more than a little difficult if you live in a terraced house or flat.”

Derek explains further: “MIRA’s hybrid vision is to lower tailpipe emissions and deliver better fuel efficiency than an equivalent diesel, at a diesel level on-cost” (the typical on-cost for a diesel powertrain is approximately £2000).

A regenerative braking system makes its debut on the MIRA hybrid. Derek explains why: “The viability of such systems requires careful analysis to ensure that the mass penalty is outweighed by the energy recovery potential. The technology has now matured to deliver a tangible economy benefit, not just a ‘feature’ for the marketers.”

The powertrain is supported by a new aero pack, reducing drag by 8% to achieve a Cd of just 0.299. Interestingly, aerodynamics makes only a small contribution to EU drive cycle calculations, due to the cycle’s overall low speed character.